diff options
Diffstat (limited to 'compiler/parampatterns.nim')
| -rw-r--r-- | compiler/parampatterns.nim | 93 |
1 files changed, 64 insertions, 29 deletions
diff --git a/compiler/parampatterns.nim b/compiler/parampatterns.nim index 0b8c8543e..944aec048 100644 --- a/compiler/parampatterns.nim +++ b/compiler/parampatterns.nim @@ -10,7 +10,8 @@ ## This module implements the pattern matching features for term rewriting ## macro support. -import strutils, ast, astalgo, types, msgs, idents, renderer, wordrecg, trees +import strutils, ast, astalgo, types, msgs, idents, renderer, wordrecg, trees, + options # we precompile the pattern here for efficiency into some internal # stack based VM :-) Why? Because it's fun; I did no benchmarks to see if that @@ -41,8 +42,8 @@ type const MaxStackSize* = 64 ## max required stack size by the VM -proc patternError(n: PNode) = - localError(n.info, errIllFormedAstX, renderTree(n, {renderNoComments})) +proc patternError(n: PNode; conf: ConfigRef) = + localError(conf, n.info, "illformed AST: " & renderTree(n, {renderNoComments})) proc add(code: var TPatternCode, op: TOpcode) {.inline.} = add(code, chr(ord(op))) @@ -53,42 +54,42 @@ proc whichAlias*(p: PSym): TAliasRequest = else: result = aqNone -proc compileConstraints(p: PNode, result: var TPatternCode) = +proc compileConstraints(p: PNode, result: var TPatternCode; conf: ConfigRef) = case p.kind of nkCallKinds: if p.sons[0].kind != nkIdent: - patternError(p.sons[0]) + patternError(p.sons[0], conf) return let op = p.sons[0].ident if p.len == 3: if op.s == "|" or op.id == ord(wOr): - compileConstraints(p.sons[1], result) - compileConstraints(p.sons[2], result) + compileConstraints(p.sons[1], result, conf) + compileConstraints(p.sons[2], result, conf) result.add(ppOr) elif op.s == "&" or op.id == ord(wAnd): - compileConstraints(p.sons[1], result) - compileConstraints(p.sons[2], result) + compileConstraints(p.sons[1], result, conf) + compileConstraints(p.sons[2], result, conf) result.add(ppAnd) else: - patternError(p) + patternError(p, conf) elif p.len == 2 and (op.s == "~" or op.id == ord(wNot)): - compileConstraints(p.sons[1], result) + compileConstraints(p.sons[1], result, conf) result.add(ppNot) else: - patternError(p) + patternError(p, conf) of nkAccQuoted, nkPar: if p.len == 1: - compileConstraints(p.sons[0], result) + compileConstraints(p.sons[0], result, conf) else: - patternError(p) + patternError(p, conf) of nkIdent: let spec = p.ident.s.normalize case spec - of "atom": result.add(ppAtom) - of "lit": result.add(ppLit) - of "sym": result.add(ppSym) + of "atom": result.add(ppAtom) + of "lit": result.add(ppLit) + of "sym": result.add(ppSym) of "ident": result.add(ppIdent) - of "call": result.add(ppCall) + of "call": result.add(ppCall) of "alias": result[0] = chr(aqShouldAlias.ord) of "noalias": result[0] = chr(aqNoAlias.ord) of "lvalue": result.add(ppLValue) @@ -97,24 +98,24 @@ proc compileConstraints(p: PNode, result: var TPatternCode) = of "nosideeffect": result.add(ppNoSideEffect) else: # check all symkinds: - internalAssert int(high(TSymKind)) < 255 + internalAssert conf, int(high(TSymKind)) < 255 for i in low(TSymKind)..high(TSymKind): if cmpIgnoreStyle(($i).substr(2), spec) == 0: result.add(ppSymKind) result.add(chr(i.ord)) return # check all nodekinds: - internalAssert int(high(TNodeKind)) < 255 + internalAssert conf, int(high(TNodeKind)) < 255 for i in low(TNodeKind)..high(TNodeKind): if cmpIgnoreStyle($i, spec) == 0: result.add(ppNodeKind) result.add(chr(i.ord)) return - patternError(p) + patternError(p, conf) else: - patternError(p) + patternError(p, conf) -proc semNodeKindConstraints*(p: PNode): PNode = +proc semNodeKindConstraints*(p: PNode; conf: ConfigRef): PNode = ## does semantic checking for a node kind pattern and compiles it into an ## efficient internal format. assert p.kind == nkCurlyExpr @@ -123,11 +124,11 @@ proc semNodeKindConstraints*(p: PNode): PNode = result.strVal.add(chr(aqNone.ord)) if p.len >= 2: for i in 1..<p.len: - compileConstraints(p.sons[i], result.strVal) + compileConstraints(p.sons[i], result.strVal, conf) if result.strVal.len > MaxStackSize-1: - internalError(p.info, "parameter pattern too complex") + internalError(conf, p.info, "parameter pattern too complex") else: - patternError(p) + patternError(p, conf) result.strVal.add(ppEof) type @@ -178,6 +179,36 @@ type arDiscriminant, # is a discriminant arStrange # it is a strange beast like 'typedesc[var T]' +proc exprRoot*(n: PNode): PSym = + var it = n + while true: + case it.kind + of nkSym: return it.sym + of nkHiddenDeref, nkDerefExpr: + if it[0].typ.skipTypes(abstractInst).kind in {tyPtr, tyRef}: + # 'ptr' is unsafe anyway and 'ref' is always on the heap, + # so allow these derefs: + break + else: + it = it[0] + of nkDotExpr, nkBracketExpr, nkHiddenAddr, + nkObjUpConv, nkObjDownConv, nkCheckedFieldExpr: + it = it[0] + of nkHiddenStdConv, nkHiddenSubConv, nkConv: + it = it[1] + of nkStmtList, nkStmtListExpr: + if it.len > 0 and it.typ != nil: it = it.lastSon + else: break + of nkCallKinds: + if it.typ != nil and it.typ.kind == tyVar and it.len > 1: + # See RFC #7373, calls returning 'var T' are assumed to + # return a view into the first argument (if there is one): + it = it[1] + else: + break + else: + break + proc isAssignable*(owner: PSym, n: PNode; isUnsafeAddr=false): TAssignableResult = ## 'owner' can be nil! result = arNone @@ -189,7 +220,7 @@ proc isAssignable*(owner: PSym, n: PNode; isUnsafeAddr=false): TAssignableResult let kinds = if isUnsafeAddr: {skVar, skResult, skTemp, skParam, skLet} else: {skVar, skResult, skTemp} if n.sym.kind in kinds: - if owner != nil and owner.id == n.sym.owner.id and + if owner != nil and owner == n.sym.owner and sfGlobal notin n.sym.flags: result = arLocalLValue else: @@ -205,7 +236,8 @@ proc isAssignable*(owner: PSym, n: PNode; isUnsafeAddr=false): TAssignableResult result = arLValue else: result = isAssignable(owner, n.sons[0], isUnsafeAddr) - if result != arNone and sfDiscriminant in n.sons[1].sym.flags: + if result != arNone and n[1].kind == nkSym and + sfDiscriminant in n[1].sym.flags: result = arDiscriminant of nkBracketExpr: if skipTypes(n.sons[0].typ, abstractInst-{tyTypeDesc}).kind in @@ -222,7 +254,10 @@ proc isAssignable*(owner: PSym, n: PNode; isUnsafeAddr=false): TAssignableResult elif compareTypes(n.typ, n.sons[1].typ, dcEqIgnoreDistinct): # types that are equal modulo distinction preserve l-value: result = isAssignable(owner, n.sons[1], isUnsafeAddr) - of nkHiddenDeref, nkDerefExpr, nkHiddenAddr: + of nkHiddenDeref: + if n[0].typ.kind == tyLent: result = arDiscriminant + else: result = arLValue + of nkDerefExpr, nkHiddenAddr: result = arLValue of nkObjUpConv, nkObjDownConv, nkCheckedFieldExpr: result = isAssignable(owner, n.sons[0], isUnsafeAddr) |